What does it mean that the least in the kingdom of heaven is greater than John the Baptist?
Matthew 11:11 (KJV):
"Verily I say unto you, Among them that are born of women there hath
not risen a greater than John the Baptist: notwithstanding he that is
least in the kingdom of heaven is greater than he."
Jesus makes an agreement with his disciples to grant them a kingdom.
It is Nisan 14th, the year 33 C.E. and Jesus had just celebrated the Lord's Super with his disciples and says to them: 28 “You are those who have stood by Me in My trials; 29 and just as My Father has granted Me a kingdom, I grant you 30 that you may eat and drink at My table in My kingdom, and you will sit on thrones judging the twelve tribes of Israel.(Luke 22:28-30 NASB)
Jesus makes an agreement/ covenant with his apostles like his Father made an agreement/ covenant with him and promises them that they will sit on thrones. This privilege was later extended to others in total about 120 followers of his, on the day of the Pentecost, by anointing them with holy spirit, the total number of those to be redeemed/purchased from mankind total one hundred and forty four thousand.(Rev. 14:1-5 NASB)
The Reward for those that conquer.
Jesus speaks of the reward to those that conquer; "The one who conquers, I will grant him to sit with me on my throne, as I also conquered and sat down with my Father on his throne. "(Rev.3;21 ESV) Although John prepared the way for Jesus , he was executed and died prior to Jesus making the agreement with his disciples, to grant them a Kingdom. Therefore as Jesus said to his disciples at verse 28 :“You are those who have stood by Me in My trials", John died and thus could not stand with Jesus -"By me in My trails."
Also Paul wrote to his close friend Timothy that: "If we endure, we will also reign with Him; If we deny Him, He also will deny us."( 2 Tim. 2:12 NASB) Again since John did not endure as Jesus did, he could not be rewarded to sit in the Kingdom of Heaven with Jesus.
And what about John and others?
Jesus said that the meek will inherit the earth , many centuries earlier, King David also wrote that the meek will to inherit the earth and live in abundance of peace. Isaiah wrote about the the New Heavens and a New Earth and , (Isaiah 65:17-25 NASB) in verse 20 writes : “No longer will there be in it an infant who lives but a few days", so every child will have the opportunity to live a safe and endless life.
Psalm 37:10-11 KJV
10 "For yet a little while, and the wicked shall not be: yea, thou
shalt diligently consider his place, and it shall not be. But the meek
shall inherit the earth; and shall delight themselves in the abundance
Jesus may have had this verse in mind when he said : "Blessed are the meek: for they shall inherit the earth." Matthew 5:35( KJV )
By means of the resurrection, (John 5:28-29) John and others will be raised from the dead and as an heir of God's Kingdom on earth, a mortal , will be lower than the least one , in the Kingdom of Heaven.
Paul applied Psalm 8 :4-6 when he wrote Hebrews 2:9 that Jesus as a mortal , was made lower than the angels: "But we do see Him who was made for a little while lower than the angels, namely, Jesus, because of the suffering of death crowned with glory and honor, so that by the grace of God He might taste death for everyone." Hebrews 2:9 ( NASB)